Sorry for the late reply
I added a file, that doesn't have a group but the mask on the hue/saturation layer is doing something weird.
If i hide the hue/saturation layer, the effect of it is not shown, the image looks untouched as expected.
but if I enable the hue/saturation layer, and if you enable/disable the mask (that is set to hide all) the image gets darker and brighter.
If the mask of the hue saturation is set to hide all, shouldnt there be 0 effect, no matter if you enable or disable the mask?
TLDR: adding a mask to a hue/saturation layer seems to overall darken the image, no matter if you have anything painted into the mask or not.